I have a Bosch 51 distributor on my 230 SL and I recently replaced points with a Hot-Spark electronic ignition kit (pertronix clone). The problem is that I cannot get the required 2-4 degrees ATDC at idle (vacuum connected). With anything less that 4-6 degrees BTDC the idle gets too low, even with full idle enrichment of FIP, and the engine would stall. With 6 or even more degrees BTDC the car idles e runs well, but I get 40 degrees advance at 3k RPM which I think is too much.
The battery is new, the coil (Bosch red coil) is new, spark plugs and cables are in good shape
Any suggestion?